Fused connecting plug having fuses which can be removed without dis-assembly of the housing and an indicating lamp for indicating a fuse disruption



' Nov. 16, 1965 3,218,413 FUSED CONNECTING PLUG HAVING FUSES WHICH CANBE REMOVED WITHOUT DISASSEMBLY OF THE HOUSING AND AN INDICATING LAMP.FOR INDICATING A FUSE DISRUPTION Filed 001,. 26, 1964 INVENTOR. RuooLFKOCH United States Patent M 3,218,413 FUSED CONNECTING PLUG HAVING FUSESWHICH CAN BE REMOVED WETHOUT DIS- ASSEMBLY OF THE HOUSING AND AN INDI-CATING LAMP FOR INDICATING A FUSE DISRUPTION Rudolf Koch, 1948 N. 26thSt., Milwaukee, Wis. Filed Oct. 26, 1964, Ser. No. 406,970 2 Claims.(Cl. ZOO-415.5)

An object of the present invention is to provide a small and compactfused plug, having electrodes or prongs extending from one end forinsertion in a multiple outlet between other plug devices and havingsockets for receiving the prongs of another plug.

It is a further object of this invention to provide such a small andcompact fused plug having internally mounted fuses which can be readilyand easily inserted and removed without disassembly of the outer body orhous- It is still a further object of the present invention to providesuch a small and compact fused plug having integrated therein a smallindicating lamp or the like for indicating disruption of one of theinternal fuses.

The fused or In-Bee-Tween Plug is used between any appliance and astandard duplex receptacle or wall plug.

If a fused plug such as this is used in connection with an electricblanket, a set of Christmas tree lights, a dehumidifier or any suchappliance that will remain unattended over long periods of time: you canbe sure that if short circuits develop in the appliance there will be amuch greater margin of safety because the In-Bee- Tween Plu=g is fusedjust above the current being used by the appliance itself.

irregularities which would not blow the larger line fuse would show upby a fuse being blown in the In-Bee- Tween Plug.

The In-BeeTween Plug has an indicator which lights up when a fuse isblown by the appliance. It is easily determined then which appliance isfaulty. Naturally the line fuse is still in operation and service iscontinuous for other appliances being fed off the same circuit.

In this way faulty operation will be discovered earlier and the dangerof fire from any particular appliance will be reduced.

The drawing furnished herewith illustrates a preferred construction ofthe present invention in which the above advantages and features as wellas others are clearly shown and described.

In the drawing:

FIG. 1 is a perspective view of a fused plug constructed in accordancewith the present invention with portions thereof broken away to showinner details of construction; and

FIG. 2 is a vertical section taken through the plug structure includingthe lamp'structure shown in FIG. 1.

Generally, the present invention is adapted to be employed as anintermediate plug to be connected into the usual well-known wall socketreceptacle or the like, not shown. In the illustrated embodiment of theinvention, the plug includes an outer two-piece molded housing 1 formedof a suitable electrical insulating material. Generally, the housing 1as shown in FIG. 1 has a pair of parallel main walls joined around theperiphery by a short side wall and selected to define a thickness whichwill be less than the space between the socket units of the conventionalwall receptacle. Such wall receptacles are well-known devices which willbe readily apparent to those skilled in the art and no furtherdescription or illustration thereof is given. An electroluminescentindicator 2 is mounted within the housing as more fully 3,218,413Patented Nov. 16, 1965 ICC described hereinafter to provide anindication of the current carrying capacity of the fused plug.Generally, a pair of plug-type electrodes 3 and 4 have one end disposedwithin the housing and project outwardly in parallel spaced relation forinsertion within the wall receptacle. The inner ends of the electrodes 3and 4 are provided with suitable laterally bent portions and are clampedwithin a suitable recess within the two-piece housing. A pair ofreceiving socket electrodes 10 is secured in spaced alignment with theelectrodes 3 and 4 and totally within the housing 1 with appropriatealigned receiving openings 11 provided in the side wall opposite that ofthe electrodes 3 and 4. The socket electrodes 14) are also clampedwithin the housing by the connection of the two-piece molded base orhousing 1.

Each of the electrodes 3, 4 and 10 are constructed with similar U-shapedend fuse holders 7 each formed as an integral lateral bent lip portionimmediately to one side of the electrode. The electrodes are mountedwith the fuse holders 7 of the aligned and associated socket and plugelectrodes lying along opposite sides of the housing 1. A conventionalfuse 6 such as the well-known fuse sold by the trademark Buss type AGX5or the like is disposed within the housing with the opposite contactends within the respective fuse holders 7. The molded base 1 adjacentthe plugs 3 and 4 is provided with an opening 5 somewhat larger than thediameter of a tubular fuse 6 for insertion of the fuse. The opposite endof the molded base 1 is provided with a small opening 9 aligned with thefuse and within which a plunger 8 formed of a suitable insulatingmaterial is slidably disposed. The fuse 6 can be removed by forcing of asuitable tool through the small opening 9 to push the plunger 8 inwardlyand force the fuse 6 outwardly through the insert opening 5 to a degreethat the end can be grasped; for example, by the persons fingers. Asimilar opening 12 is provided on the opposite end of the housing 1,which is of course symmetrically for-med.

The indicator 2 is held completely within the housing 1 such that thethin construction is maintained whereby the plug can be inserted in amultiple socket receptacle without interfering with the insertion ofother conventional plugs. Preferably, the indicator 2 is of thewellknown electroluminescent variety and is only briefly described ashaving an outer glass or plastic window 13 forming the covering for aviewing opening in the housing 1. A transparent conductor 14 such as tinoxide is integrally formed on the inner surface of the glass with asuitable electroluminescent powder deposit 15 disposed between conductor14 and a metallic conductor 16. Suitable spring contacts 17 are providedto the opposite surfaces and curl around upon a base insulator material18 and spaced in accordance with the spacing between the correspondingplug electrode 3 and the corresponding socket electrode 11). Inassembly, the indicator 2 is held within the housing 1 with theelectrodes 1'7 clamped downwardly onto the members by the housing whichis provided with an opening generally corresponding to the diameter ofthe glass or the like.

The present invention thus provides a highly satisfactory plug which canbe inserted into the wall receptacle to provide separate fusing for theindividual appliance connected through the socket electrodes of theplug 1. The plug of the present invention can fit between other plugs inmultiple convenience outlets and does not require outside wiring orscrews for interconnection of the appliance. The fuses are readilyremoved and replaced while maintained within the body. The indicator isbuilt in to provide indication of unwanted circuit openings.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim: 1. A fused connecting plug for insertion in one of the socketunits of a multiple unit receptacle, comprising a fiat rectangularinsulating housing having a pair of parallel main walls joined aroundthe periphery by a short side wall to define a thickness less than thespacing between the socket units of a receptacle,

a pair of laterally spaced plug prongs secured within the housing andprojecting outwardly through the side Wall,

a pair of correspondingly laterally spaced prong receiving socketsaligned with and spaced from the plug prongs, said housing havingopening means aligned with the sockets for insertion of prongs into thesockets,

a fuse disposed to one side of an aligned prong and socket in saidhousing and connected thereto to complete the circuit therebetween, and

a thin lamp means mounted in the housing between the parallel main wallsand spanning the aligned 4: prong and socket connected to the fuse andthereby being connected in parallel with the fuse and be ing illuminatedupon disruption of the 'fuse, said housing having a viewing opening fordetection of said illumination.

2. The fused connecting plug of claim 1, wherein said lamp means is anelectroluminescent unit of a thin wafer type construction mountedparallel to the parallel main walls and having a pair of electrodesrespectively engaging the aligned prong and socket.

References Cited by the Examiner UNITED STATES PATENTS 2,128,418 8/1938LaMar a 200121 2,164,658 7/1939 Lyon 200-421 2,649,522 8/1953 Marcus2001l5 2,988,617 6/1961 Graziosi 20()115 FOREIGN PATENTS 575,936 3/ 1946Great Britain.

ROBERT K. SCHAEFER, Acting Primary Examiner.

1. A FUSED CONNECTING PLUG FOR INSERTION IN ONE OF THE SOCKET UNITS OF AMULTIPLE UNIT RECEPTACLE, COMPRISING A FLAT RECTANGULAR INSULATINGHOUSING HAVING A PAIR OF PARALLEL MAIN WALLS JOINED AROUND THE PERIPHERYBY A SHORT SIDE WALL TO DEFINE A THICKNESS LESS THAN THE SPACING BETWEENTHE SOCKET UNITS OF A RECEPTACLE, A PAIR OF LATEALLY SPACED PLUG PRONGSSECURED WITHIN THE HOUSING AND PROJECTING OUTWARDLY THROUGH THE SAIDWALL, A PAIR OF CORRESPONDINGLY LATERALLY SPACED PRONG RECEIVING SOCKETSALIGNED WITH AND SPACED FROM THE PLUG PRONGS, SAID HOUSING HAVINGOPENING MEANS ALIGNED WITH THE SOCKETS FOR INSERTION OF PRONGS INTO THESOCKETS, A FUSE DISPOSED TO ONE SIDE OF AN ALIGNED PRONG AND SOCKET INSAID HOUSING AND CONNECTED THERETO TO COMPLETE THE CIRCUIT THEREBETWEEN,AND A THIN LAMP MEANS MOUNTED IN THE HOUSING BETWEEN THE PARALLEL MAINWALLS AND SPANNING THE ALIGNED PRONG AND SOCKET CONNECTED TO THE FUSEAND THEREBY BEING CONNECTED IN PARALLEL WITH THE FUSE AND BEINGILLUMINATED UPON DISRUPTION OF THE FUSE, SAID HOUSING HAVING A VIEWINGOPENING FOR DETECTION OF SAID ILLUMINATION.